الفهرس 
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Abstract
It is well known that the uncontrolled growth in the world population coupled with industrialization has made a gap between demand and production of the vegetable oil. Despite the fact that Egypt is an agrarian economy, it is unable to produce the edible oils sufficient for the domestic needs where the Egyptian oils productions do not exceed 18% of requirements of them. Therefore, we are being now in a greet need of a new source of edible oil to reach the self-sufficiency of our needs from edible oils.
As Egypt has fast fertile plains and reclaimed soils land, a good irrigation sources and a variable better climate conditions, therefore, the Moringa species plants would be potentially valuable crop yielding useful edible oil characteristics with a better healthy safe and nutritional quality. This might be a good solution to narrow the gap of our needs.
For this reasons Moringa oleifera L. were be chosen as a new source for edible oil as it could be grow successfully in Egypt. These studies were carried out in order to evaluate the extraction of Moringa oleifera seed oil by using the aqueous enzymatic extraction method using the olive centrifugal mill and to investigate the quality of obtained oil by determining the physical and chemical properties, the oxidative stability and fatty acid composition of extracted Moringa oleifera oil.
Also, the effect of using extracted Moringa oleifera oil as fat replacer of shortening and animal fat in preparing cup cake and meatball respectively was evaluated.
1-The analysis of Moringa oleifera seeds:
The tested Moringa oleifera seed were characterized by containing a much higher content of protein where seeds, seed kernel and seed shell contained 40.84%, 42.29% and 7.72% of crude protein, respectively. Also the oil contents of seeds, seed kernel and seed shell was 33.48%, 40.87% and 3.63%, respectively.
Crude fiber, Ash and carbohydrate content of Moringa oleifera seed were 3.47%, 4.17% and 11.55%, respectively. In the same time, it could be reported that, Moringa oleifera seed cake considered to be a good source of protein (42.50%) which could be added to poultry feed as a protein source.
Thus, Moringa oleifera seed kernel could be potentially a good source of protein and oil, which should be exploited to determine if they are commercially viable and utilized towards human nutrition field.
2-The Physico-chemical parameters of Moringa oleifera seeds oil:
- The extracted Moringa oleifera seed oil under investigation were found to be a very good physical quality represented in the refractive index (1.4665), specific gravity (0.9122cm³/gm), viscosity (11776 CP), smoke point (207˚C) and color (35Y, 3.6R).
- Also, extracted Moringa oleifera seed oil characterized with an excellent chemical properties including acidity (1.4%), sapnofication number (194.7%), unsapnofication matter (0.54%), total tocopherols (71.0 ppm) and total phenols (466.8 ppm).
3-The oxidative stability of Moringa oleifera seeds oil:
The extracted Moringa oleifera seed oil exhibited a very higher good oxidative stability and healthy safe quality as showing by peroxide value (5.44 meqO2/kg), the TBA value at 532 nm (0.874mg malonaldhyde/kg), a very longer induction period (304.8 hr.) at 100˚C and the specific extension at 232 and 270 nm (1.3720- 0.1018), respectively.
4-The fatty acid composition of Moringa oleifera seeds oil:
The total saturated fatty acids of extracted Moringa oleifera seed oil were 22.40%, the major saturated fatty acids was Palmitic acid with 7.79% followed by Behenic acid with a substantial amount of 6.87%. Also, it found that the total unsaturated fatty acids were 77.61 %; the dominant unsaturated fatty acid was Oleic acid with 72.29 %. These mean that, extracted MOO is desirable in terms of nutrition and high stability during cooking and frying process due to the higher level of monoenoic fatty acid especially the oleic acid which is less prone to the oxidation than polyenoic acids.
5-The Effect of replacing shortening by Moringa oleifera oil on cup cake quality:
a- Chemical analysis of cupcake at zero time:
It could be concluded that, replacing extracted Moringa oleifera seed oil in preparing cup cake with extracted MOO with level of 50% tended to increase moisture content of prepared cup cake, whilst moisture content of prepared cup cake with level of 25 and 75% of extracted MOO was decreased in comparison with control cup cake samples contained 100% shortening.
b- Physical characteristics at zero time:
There was an increase in the specific volume of prepared cup cake samples as the shortening was replaced by extracted Moringa oleifera seed oil with level 50% and 75%, respectively.
These means that adding Moringa oleifera seed oil caused an increase in the cup cake volume in relation to the weight.
c-The replacement of shortening in cup cake sample by Moringa oleifera seed oil caused an increasing in the acid values at 75% followed by 50%, 25% and control samples, respectively, during the storage period at room temperature.
d- from the results obtained it could concluded that the highest rate of increasing for the POV was that obtained of the control cup cake samples followed by cup cake samples prepared with replacing shortening by the 50% and 75% of extracted Moringa oleifera seed oil, respectively, where the lowest rate of increasing for the POV was obtained for cup cakes samples prepared by replacing shortening with 25% of Moringa oleifera seed oil at the end of storage period.
e- It could be concluded that the TBA values of cup cake samples was increased as the storage period increase till 7 days with a high rate of increasing for the control cup cake samples contained 100% shortening followed by cup cake samples contained 75%,50% and 25% extracted Moringa oleifera seed oil as shortening replacer, in respect.
f- There was a decrease in the moisture content of the baked cup cake as the storage period increase from zero to 7 days. The highest rate of decrease in moisture content was obtained for control cup cake sample followed by cup cake samples contained level of 25%, 75% and 50% Moringa oleifera seed oil as shortening replacer, respectively.
g- The staling rates of prepared cup cakes were determined by Alkaline Water Retention Capacity (AWRC). There was a reduction in the AWRC values in all prepared cup cake samples at the end of the storage period.
The highest rate of reduction obtained with the control cup cake samples followed by cup cake samples prepared by replacing shortening with 50%, 25% and 75% Moringa oleifera seed oil, respectively.
h- The sensory evaluation of the cup cakes proved that the replacement of shortening with 25% of Moringa oleifera seed oil gave an overall acceptability than the other replacement percentage. On the contrary, the control samples (without addition of Moringa oleifera seed oil) had the lower scores for most sensory properties.
6-The Effect of replacing animal fat by Moringa oleifera oil on the quality characteristics of processed meatballs:
There was an increase in the cooking loss under the different treatment of Moringa oleifera seed oil as the storing period increase. The higher increase in cooking loss was that with replacing of animal fat with 25% Moringa oleifera seed oil followed by 50% as well as that with control samples. This was true under different storing periods of zero, 2 and 4 days of storage whilst the control samples containing 100% animal fat showed a superiority in cooking loss percent at 6,8 and 10 days in comparison to meatball samples prepared by replacing animal fat with 25 and 50% of extracted Moringa oleifera seed oil.
Also there was an increase in the acid value at the end of storage period. The highest acid values was obtained in the control meatball samples followed by the samples containing 50% then 25% Moringa oleifera seed oil as animal fat replacer.
There was a gradually increase in the TBA values as storage period increase to 6, 8 and 10 days. This was true under the control meatball sample which contain 100% animal fat followed by the meatball samples containing 50%, 25% Moringa oleifera seed oil as animal fat replacer, respectively. There is no significant difference between the TBA values of both samples containing 25% and 50% Moringa oleifera seed oil.
There are no significant differences in the overall acceptability scores with the meatballs samples containing 25% and 50% Moringa oleifera seed oil as animal fat replacer.
It could be concluded that, the replacement of animal fat in meatballs by 25% and 50% Moringa oil caused a significant increase in the overall acceptability scores in comparison with the control meatballs samples.
Thus it could be concluded that:
1-Success of using olive centrifugal mill in extraction of Moringa oleifera seeds without any modification on any part of the centrifugal mill parts.
2-Using protease enzyme in the extraction method could be improving the quality of Moringa oleifera oil.
3-Moringa oleifera oil could be utilized successfully as a source of edible oil where it improves the oxidative stability and the sensory properties of both cup cake and meatball processed.